source: trunk/tools/designer/editor/parenmatcher.cpp

/**********************************************************************
** Copyright (C) 2005-2007 Trolltech ASA.  All rights reserved.
**
** This file is part of Qt Designer.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
**
** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition
** licenses may use this file in accordance with the Qt Commercial License
** Agreement provided with the Software.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
** See http://www.trolltech.com/gpl/ for GPL licensing information.
** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for
**   information about Qt Commercial License Agreements.
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** not clear to you.
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**********************************************************************/

#include "parenmatcher.h"
#include "paragdata.h"

#include "qtextedit.h"
#include <private/qrichtext_p.h>
#include <qapplication.h>

ParenMatcher::ParenMatcher()
{
    enabled = TRUE;
}

bool ParenMatcher::match( QTextCursor *cursor )
{
    if ( !enabled )
        return FALSE;
    bool ret = FALSE;

    QChar c( cursor->paragraph()->at( cursor->index() )->c );
    bool ok1 = FALSE;
    bool ok2 = FALSE;
    if ( c == '{' || c == '(' || c == '[' ) {
        ok1 = checkOpenParen( cursor );
        ret = ok1 || ret;
    } else if ( cursor->index() > 0 ) {
        c = cursor->paragraph()->at( cursor->index() - 1 )->c;
        if ( c == '}' || c == ')' || c == ']' ) {
            ok2 = checkClosedParen( cursor );
            ret = ok2 || ret;
        }
    }

    return ret;
}

bool ParenMatcher::checkOpenParen( QTextCursor *cursor )
{
    if ( !cursor->paragraph()->extraData() )
        return FALSE;
    ParenList parenList = ( (ParagData*)cursor->paragraph()->extraData() )->parenList;

    Paren openParen, closedParen;
    QTextParagraph *closedParenParag = cursor->paragraph();

    int i = 0;
    int ignore = 0;
    bool foundOpen = FALSE;
    QChar c = cursor->paragraph()->at( cursor->index() )->c;
    for (;;) {
        if ( !foundOpen ) {
            if ( i >= (int)parenList.count() )
                goto bye;
            openParen = parenList[ i ];
            if ( openParen.pos != cursor->index() ) {
                ++i;
                continue;
            } else {
                foundOpen = TRUE;
                ++i;
            }
        }
        
        if ( i >= (int)parenList.count() ) {
            for (;;) {
                closedParenParag = closedParenParag->next();
                if ( !closedParenParag )
                    goto bye;
                if ( closedParenParag->extraData() &&
                     ( (ParagData*)closedParenParag->extraData() )->parenList.count() > 0 ) {
                    parenList = ( (ParagData*)closedParenParag->extraData() )->parenList;
                    break;
                }
            }
            i = 0;
        }
        
        closedParen = parenList[ i ];
        if ( closedParen.type == Paren::Open ) {
            ignore++;
            ++i;
            continue;
        } else {
            if ( ignore > 0 ) {
                ignore--;
                ++i;
                continue;
            }

            int id = Match;
            if ( c == '{' && closedParen.chr != '}' ||
                 c == '(' && closedParen.chr != ')' ||
                 c == '[' && closedParen.chr != ']' )
                id = Mismatch;
            cursor->document()->setSelectionStart( id, *cursor );
            int tidx = cursor->index();
            QTextParagraph *tstring = cursor->paragraph();
            cursor->setParagraph( closedParenParag );
            cursor->setIndex( closedParen.pos + 1 );
            cursor->document()->setSelectionEnd( id, *cursor );
            cursor->setParagraph( tstring );
            cursor->setIndex( tidx );
            return TRUE;
        }
    }

 bye:
    return FALSE;
}

bool ParenMatcher::checkClosedParen( QTextCursor *cursor )
{
    if ( !cursor->paragraph()->extraData() )
        return FALSE;
    ParenList parenList = ( (ParagData*)cursor->paragraph()->extraData() )->parenList;

    Paren openParen, closedParen;
    QTextParagraph *openParenParag = cursor->paragraph();

    int i = (int)parenList.count() - 1;
    int ignore = 0;
    bool foundClosed = FALSE;
    QChar c = cursor->paragraph()->at( cursor->index() - 1 )->c;
    for (;;) {
        if ( !foundClosed ) {
            if ( i < 0 )
                goto bye;
            closedParen = parenList[ i ];
            if ( closedParen.pos != cursor->index() - 1 ) {
                --i;
                continue;
            } else {
                foundClosed = TRUE;
                --i;
            }
        }
        
        if ( i < 0 ) {
            for (;;) {
                openParenParag = openParenParag->prev();
                if ( !openParenParag )
                    goto bye;
                if ( openParenParag->extraData() &&
                     ( (ParagData*)openParenParag->extraData() )->parenList.count() > 0 ) {
                    parenList = ( (ParagData*)openParenParag->extraData() )->parenList;
                    break;
                }
            }
            i = (int)parenList.count() - 1;
        }
        
        openParen = parenList[ i ];
        if ( openParen.type == Paren::Closed ) {
            ignore++;
            --i;
            continue;
        } else {
            if ( ignore > 0 ) {
                ignore--;
                --i;
                continue;
            }
        
            int id = Match;
            if ( c == '}' && openParen.chr != '{' ||
                 c == ')' && openParen.chr != '(' ||
                 c == ']' && openParen.chr != '[' )
                id = Mismatch;
            cursor->document()->setSelectionStart( id, *cursor );
            int tidx = cursor->index();
            QTextParagraph *tstring = cursor->paragraph();
            cursor->setParagraph( openParenParag );
            cursor->setIndex( openParen.pos );
            cursor->document()->setSelectionEnd( id, *cursor );
            cursor->setParagraph( tstring );
            cursor->setIndex( tidx );
            return TRUE;
        }
    }

 bye:
    return FALSE;
}